Multiprotocol Label Switching (MPLS) has gradually become a mainstream technology as it has capability of supporting multilayer label nesting and end-to-end Resource ReSerVation Protocol-Traffic Engineering (RSVP-TE), and good Quality of Service (QoS). However, the MPLS is incapable of supporting Time Division Multiplex (TDM) switching or Wavelength Division Multiplexing (WDM) switching.
With the development of technology, the problem is solved through extending RSVP-TE signaling, and the MPLS is further developed into the recent technology of Generalized Multiprotocol Label Switching (GMPLS).
When a data communication device in a data communication network, for example, a router (in the following illustration, a router is used as an example, but the data communication device applicable to the present invention is not limited to the router, for example, the data communication device may also be a three-layer switch or other devices with a routing function) supports the GMPLS, and all optical communication devices in an optical network support the GMPLS, the router and the optical communication devices can exchange transmission path information on a control plane. An optical communication device can establish a bi-directional GMPLS User-Network Interface (UNI) tunnel located between a source router and a destination router corresponding to a destination address according to information transmitted by the router and requirements of the router (such as the destination address, a bandwidth, and a QoS parameter). After the GMPLS UNI tunnel is successfully established, firstly, the tunnel is required to be declared to other routers in the network through the router in a manner of Forwarding Adjacency (FA).
Therefore, for other routers in the data communication network, the GMPLS UNI tunnel participates in routing computation and path selection of an MPLS tunnel after corresponding reconstruction on the control plane of a network protocol IP/MPLS, and thereby an IP/MPLS service is born over the GMPLS UNI tunnel. On a forwarding plane, a forwarding table generated by the GMPLS UNI tunnel is inserted in an existing IP/MPLS forwarding process. The forwarding table is used to indicate an actual physical egress interface of the GMPLS UNI tunnel, and put a label of the GMPLS UNI tunnel on a data packet, thereby bearing the IP/MPLS service over the GMPLS UNI tunnel and implementing forwarding of the IP/MPLS service. Eventually, the data packet sent from the router carries a layer of specific label of the GMPLS UNI tunnel (that is, a logical interface of the GMPLS UNI tunnel).
During the implementation of the present invention, the inventor finds that the prior art at least has the following disadvantages:
In one aspect, in order to bear an IP/MPLS service over a GMPLS UNI tunnel using a router in a data communication network, an IP/MPLS control plane is required to be reconstructed as follows: The GMPLS UNI tunnel is required to be declared out first in a manner of FA. An IP routing module in the router is required to perform new processing on the new tunnel during routing computation. An MPLS protocol module in the router is required to be reconstructed, so that the new tunnel participates in path selection of an MPLS tunnel.
In another aspect, a forwarding plane of the router is required to be reconstructed, that is, an existing forwarding process of IP/MPLS is required to be modified, and a process of inserting a GMPLS UNI tunnel table is added, which is very difficult for a forwarding engine based on an Application Specific Integrated Circuits (ASIC) chip in the router.
In further another aspect, on a source router, one more layer of label is required to be encapsulated on the forwarding plane, and one more level of forwarding table is required to be searched, thereby lowering forwarding performance; and on a receiving end, since one more layer of label is required to be processed, the forwarding performance is also affected.